Patient information · Gastroenterology
Diverticular disease
and the difference when it becomes diverticulitis
Diverticula are small pouches that form in the wall of the large bowel. They are extremely common with age and usually cause nothing at all. Diverticulitis is what happens when one becomes inflamed or infected — a different situation with different urgency.
Go to an emergency department if you have
- severe abdominal pain with fever, particularly in the lower left
- a rigid, board-like or exquisitely tender abdomen
- heavy rectal bleeding, or bleeding with dizziness or faintness
- persistent vomiting and inability to pass wind or open your bowels
- air or faeces in your urine, or urine coming from the vagina
- confusion, rapid heartbeat or feeling seriously unwell
A perforated diverticulum causes peritonitis and needs emergency surgery. Diverticular bleeding can be sudden and heavy. Air or stool in the urine suggests a fistula between bowel and bladder. In an emergency call 999, or go to the Royal London Hospital Emergency Department, Whitechapel Road, London E1 1FR.
Three different things
- Diverticulosis — the pouches are present but causing nothing. Found incidentally on a scan or colonoscopy. Very common: around half of people by 60. No treatment needed.
- Diverticular disease — the pouches cause intermittent lower abdominal pain, usually left-sided, with bloating and altered bowel habit, but no inflammation.
- Diverticulitis — a pouch becomes inflamed or infected, causing more constant and severe pain, tenderness, fever and feeling unwell. This needs treating.
The nuts and seeds advice was wrong
For decades people were told to avoid nuts, seeds, popcorn and sweetcorn in case they lodged in a diverticulum. Large studies have since found no association whatsoever — if anything, people eating more nuts had fewer episodes. There is no need to avoid them. If you have been restricting your diet on this basis for years, you can stop.
Managing an episode of diverticulitis
- Mild, uncomplicated cases are increasingly managed without antibiotics, with fluids, simple pain relief and rest — the evidence supports this in selected people.
- Antibiotics are used where you are systemically unwell, immunosuppressed, or have significant other conditions.
- Clear fluids or a low-fibre diet for a few days during an acute episode, then return to a normal high-fibre diet as it settles — not the other way round.
- Paracetamol for pain. Avoid anti-inflammatories and opioids, both of which increase the risk of perforation.
- Most uncomplicated episodes settle within a week.
Preventing recurrence
- A high-fibre diet between episodes — wholegrains, fruit, vegetables, pulses. Increase gradually over several weeks to avoid bloating, and drink more as you do.
- Regular exercise, which reduces recurrence.
- Stopping smoking, and maintaining a healthy weight.
- Avoiding constipation and straining.
- A fibre supplement if diet alone is not enough.
Follow-up and surgery
After a first episode of diverticulitis, a colonoscopy or CT colonography is usually recommended a few weeks later — not because diverticulitis causes cancer, but because bowel cancer can present identically and needs excluding.
Surgery to remove the affected segment is reserved for complications, for fistulas or narrowing, or for people with frequent disabling recurrences. It is no longer recommended simply on the basis of having had two episodes.
Book an appointment if you have lower abdominal pain with a change in bowel habit, have had an episode of diverticulitis and not been followed up, or have any rectal bleeding. We offer gastroenterology review, and arrange CT and colonoscopy through our partners.
Gastroenterology and fast CT access
Seven days a week, 9am–7pm, on Whitechapel Road.
Tower Bridge Hospital London
97–99 Whitechapel Road, London E1 1DT
WhatsApp 07903 284 189
info@mhwclinic.co.uk
Open Mon–Sat, 9am–7pm (closed Sundays until September)
In an emergency
Call 999, or go to the Royal London Hospital Emergency Department, Whitechapel Road, London E1 1FR.
When we are closed and it is not an emergency
Call NHS 111 or visit 111.nhs.uk.